Pub Date : 2025-12-17DOI: 10.1016/j.scriptamat.2025.117140
Jee-Hyun Kang, Jeong-Moo Oh
Since Cottrell and Bilby first proposed a kinetic model for strain aging, many refinements have been introduced. In particular, Harper’s model gained attention for BCC steels because it additionally considered the depletion of interstitial atoms in the matrix, which is significant in these alloys. However, for FCC-based steels, Harper’s consideration becomes insufficient owing to their high interstitial solubility; sites adjacent to dislocations become saturated with interstitials more rapidly than the matrix is depleted. In this study, an integrated model was developed by incorporating both Harper’s and Hartley’s considerations. The proposed model was shown to reproduce the main features observed in nitrogen-bearing austenitic stainless steels. More importantly, it converges to Harper’s model under low interstitial concentrations, as in BCC steels, thereby providing a unified kinetic framework for static strain aging across both lattice types.
{"title":"Strain aging kinetics in FCC steels: site saturation vs matrix depletion","authors":"Jee-Hyun Kang, Jeong-Moo Oh","doi":"10.1016/j.scriptamat.2025.117140","DOIUrl":"10.1016/j.scriptamat.2025.117140","url":null,"abstract":"<div><div>Since Cottrell and Bilby first proposed a kinetic model for strain aging, many refinements have been introduced. In particular, Harper’s model gained attention for BCC steels because it additionally considered the depletion of interstitial atoms in the matrix, which is significant in these alloys. However, for FCC-based steels, Harper’s consideration becomes insufficient owing to their high interstitial solubility; sites adjacent to dislocations become saturated with interstitials more rapidly than the matrix is depleted. In this study, an integrated model was developed by incorporating both Harper’s and Hartley’s considerations. The proposed model was shown to reproduce the main features observed in nitrogen-bearing austenitic stainless steels. More importantly, it converges to Harper’s model under low interstitial concentrations, as in BCC steels, thereby providing a unified kinetic framework for static strain aging across both lattice types.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"274 ","pages":"Article 117140"},"PeriodicalIF":5.6,"publicationDate":"2025-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-16DOI: 10.1016/j.scriptamat.2025.117124
Shubhangini Yadav, Varun A. Baheti
The diffusion parameters are currently unavailable in the Co–Zn system, and are estimated in the present study based on the reported data. Molar volume () is an essential prerequisite to estimate diffusion parameters. Interestingly, the deviation in has been noticed as (108 %) and (3 %) from ideality. The role of such a huge deviation on the estimated diffusion parameters has also been unexplored to date. Our analysis indicates the combined role of composition, , and layer thickness on the estimated diffusion parameters. This discussion suggests a prominent role of on the presented variation of the integrated interdiffusion coefficients at 250–400 °C. The activation energies for interdiffusion in and phases are estimated as 923 and 721 kJ/mol, respectively. The relatively low activation energy indicates that the phases grow by grain boundary diffusion in this system.
{"title":"A prominent role of molar volume on the estimated diffusion parameters in Cobalt–Zinc system: Revisited","authors":"Shubhangini Yadav, Varun A. Baheti","doi":"10.1016/j.scriptamat.2025.117124","DOIUrl":"10.1016/j.scriptamat.2025.117124","url":null,"abstract":"<div><div>The diffusion parameters are currently unavailable in the Co–Zn system, and are estimated in the present study based on the reported data. Molar volume (<span><math><msub><mi>V</mi><mi>m</mi></msub></math></span>) is an essential prerequisite to estimate diffusion parameters. Interestingly, the deviation in <span><math><msub><mi>V</mi><mi>m</mi></msub></math></span> has been noticed as <span><math><mrow><mstyle><mi>Δ</mi></mstyle><msubsup><mi>V</mi><mi>m</mi><msub><mi>γ</mi><mn>1</mn></msub></msubsup></mrow></math></span> (<span><math><mo>+</mo></math></span>108 %) and <span><math><mrow><mstyle><mi>Δ</mi></mstyle><msubsup><mi>V</mi><mi>m</mi><msub><mi>γ</mi><mn>2</mn></msub></msubsup></mrow></math></span> (<span><math><mo>−</mo></math></span>3 %) from ideality. The role of such a huge <span><math><msub><mi>V</mi><mi>m</mi></msub></math></span> deviation on the estimated diffusion parameters has also been unexplored to date. Our analysis indicates the combined role of composition, <span><math><msub><mi>V</mi><mi>m</mi></msub></math></span>, and layer thickness on the estimated diffusion parameters. This discussion suggests a prominent role of <span><math><msub><mi>V</mi><mi>m</mi></msub></math></span> on the presented variation of the integrated interdiffusion coefficients at 250–400 °C. The activation energies for interdiffusion in <span><math><msub><mi>γ</mi><mn>1</mn></msub></math></span> and <span><math><msub><mi>γ</mi><mn>2</mn></msub></math></span> phases are estimated as 92<span><math><mo>±</mo></math></span>3 and 72<span><math><mo>±</mo></math></span>1 kJ/mol, respectively. The relatively low activation energy indicates that the phases grow by grain boundary diffusion in this system.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"274 ","pages":"Article 117124"},"PeriodicalIF":5.6,"publicationDate":"2025-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-16DOI: 10.1016/j.scriptamat.2025.117142
Shuaiqi Wang , Guisheng Zou , Jinpeng Huo , Chengjie Du , Rongbao Du , Dejian Li , Shunfeng Han , Bofu Li , Lei Liu
Advanced electronic packaging requires highly dense sintered Cu interconnects for serving under extreme conditions. However, densification of nano-Cu is typically limited by insufficient driving force from surface energy during final sintering stage. This study presented a creep strategy to promote atomic flow, facilitating the final-stage densification. In conditions of 300°C/75 MPa, densification rate of fine-grained Cu (370 nm) was approximately 8 times higher than coarse-grained Cu (1050 nm). Theoretical analysis revealed that this enhancement was attributed to activation of grain boundary diffusion (Coble) creep, with an activation energy of 89.11 kJ/mol, and demonstrating nanocrystalline acceleration effect. Using this approach, sintered Cu density was improved from 88.15% to 95.29% within 1 min. Furthermore, a transition of creep mechanisms was observed at lower temperatures (160–250 °C), where the activation energy decreased to 14.19 kJ/mol and the influence of grain size became negligible. A critical stress threshold for densification was also identified.
{"title":"Nanocrystalline-accelerated grain boundary diffusion creep for enhanced densification rate of nano-Cu sintering","authors":"Shuaiqi Wang , Guisheng Zou , Jinpeng Huo , Chengjie Du , Rongbao Du , Dejian Li , Shunfeng Han , Bofu Li , Lei Liu","doi":"10.1016/j.scriptamat.2025.117142","DOIUrl":"10.1016/j.scriptamat.2025.117142","url":null,"abstract":"<div><div>Advanced electronic packaging requires highly dense sintered Cu interconnects for serving under extreme conditions. However, densification of nano-Cu is typically limited by insufficient driving force from surface energy during final sintering stage. This study presented a creep strategy to promote atomic flow, facilitating the final-stage densification. In conditions of 300°C/75 MPa, densification rate of fine-grained Cu (370 nm) was approximately 8 times higher than coarse-grained Cu (1050 nm). Theoretical analysis revealed that this enhancement was attributed to activation of grain boundary diffusion (Coble) creep, with an activation energy of 89.11 kJ/mol, and demonstrating nanocrystalline acceleration effect. Using this approach, sintered Cu density was improved from 88.15% to 95.29% within 1 min. Furthermore, a transition of creep mechanisms was observed at lower temperatures (160–250 °C), where the activation energy decreased to 14.19 kJ/mol and the influence of grain size became negligible. A critical stress threshold for densification was also identified.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"274 ","pages":"Article 117142"},"PeriodicalIF":5.6,"publicationDate":"2025-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-15DOI: 10.1016/j.scriptamat.2025.117141
Qiyue Zhang , Yang Chen , Bin Liu , Ruiqian Zhang , Qihong Fang , Peter K. Liaw , Jia Li
Refractory multi-principal element alloys (RMPEAs) exhibit outstanding irradiation resistance performance owing to severe lattice distortion and short-range order (SRO). Nevertheless, the influence of SRO on the plastic flow behavior of irradiated RMPEAs remains unclear, hindering development of high radiation-resistant RMPEA. Here, the origin and evolution of defect-free channels in HfNbTa RMPEA is revealed via hybrid MC/MD simulation and discrete dislocation dynamics coupled with random field theory. In HfNbTa RMPEA possessing SRO, a relatively large quantity of narrow defect-free channels alleviates plastic flow localization. The probabilistic distribution of dislocation cross-slip events indicates that SRO expands the high-probability regions for cross-slip, increasing the longitudinal distance traversed by a single dislocation through double cross-slip. This feature enables dislocation loops to escape interactions with dislocations, thereby reducing defect-free channel width and improving irradiation resistance. These findings provide insights into the role of SRO in mitigating irradiation damage and guide the design of irradiation-stable RMPEAs.
{"title":"Short-range order governs plastic flow localization in irradiated multi-principal element alloys","authors":"Qiyue Zhang , Yang Chen , Bin Liu , Ruiqian Zhang , Qihong Fang , Peter K. Liaw , Jia Li","doi":"10.1016/j.scriptamat.2025.117141","DOIUrl":"10.1016/j.scriptamat.2025.117141","url":null,"abstract":"<div><div>Refractory multi-principal element alloys (RMPEAs) exhibit outstanding irradiation resistance performance owing to severe lattice distortion and short-range order (SRO). Nevertheless, the influence of SRO on the plastic flow behavior of irradiated RMPEAs remains unclear, hindering development of high radiation-resistant RMPEA. Here, the origin and evolution of defect-free channels in HfNbTa RMPEA is revealed via hybrid MC/MD simulation and discrete dislocation dynamics coupled with random field theory. In HfNbTa RMPEA possessing SRO, a relatively large quantity of narrow defect-free channels alleviates plastic flow localization. The probabilistic distribution of dislocation cross-slip events indicates that SRO expands the high-probability regions for cross-slip, increasing the longitudinal distance traversed by a single dislocation through double cross-slip. This feature enables dislocation loops to escape interactions with dislocations, thereby reducing defect-free channel width and improving irradiation resistance. These findings provide insights into the role of SRO in mitigating irradiation damage and guide the design of irradiation-stable RMPEAs.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"274 ","pages":"Article 117141"},"PeriodicalIF":5.6,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-12DOI: 10.1016/j.scriptamat.2025.117138
German Samolyuk, Amit Shyam, Mina Yoon
There are no general approaches for predicting the effect of solutes on electrical resistivity changes in aluminum (Al) solid solutions. Here, we introduce a first principles-based approach for predicting temperature-dependent electrical resistivity of Al solid solutions. A combination of electronic structure methods was applied to calculate electronic scattering effects on chemical disorder and temperature induced atomic vibrations or phonons. Our calculations are validated by contrasting experimental resistivity measurements for two elements in Al solid solution: at 0.3 at. % concentration, Sn (an sp-valence solute) increases the residual resistivity by 0.2 , whereas Zr (a d-valence solute) causes a 2.5 increase. This trend may deviate for solute elements in Al that form semiconductors in pure state, like Si. Our findings provide an understanding of the role of valence electron character of solute atoms in determining electrical resistivity of Al alloys.
{"title":"A first principles approach for determining solute effect on electrical resistivity of Aluminum solid solution","authors":"German Samolyuk, Amit Shyam, Mina Yoon","doi":"10.1016/j.scriptamat.2025.117138","DOIUrl":"10.1016/j.scriptamat.2025.117138","url":null,"abstract":"<div><div>There are no general approaches for predicting the effect of solutes on electrical resistivity changes in aluminum (Al) solid solutions. Here, we introduce a first principles-based approach for predicting temperature-dependent electrical resistivity of Al solid solutions. A combination of electronic structure methods was applied to calculate electronic scattering effects on chemical disorder and temperature induced atomic vibrations or phonons. Our calculations are validated by contrasting experimental resistivity measurements for two elements in Al solid solution: at 0.3 at. % concentration, Sn (an <em>sp-</em>valence solute) increases the residual resistivity by 0.2 <span><math><mrow><mi>μ</mi><mstyle><mi>Ω</mi></mstyle><mo>·</mo><mi>m</mi></mrow></math></span>, whereas Zr (a d-valence solute) causes a 2.5 <span><math><mrow><mi>μ</mi><mstyle><mi>Ω</mi></mstyle><mo>·</mo><mi>m</mi></mrow></math></span> increase. This trend may deviate for solute elements in Al that form semiconductors in pure state, like Si. Our findings provide an understanding of the role of valence electron character of solute atoms in determining electrical resistivity of Al alloys.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"274 ","pages":"Article 117138"},"PeriodicalIF":5.6,"publicationDate":"2025-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145735021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-11DOI: 10.1016/j.scriptamat.2025.117135
Zipeng Xu , Fadi Abdeljawad , Gregory S. Rohrer
The anisotropic grain boundary stiffness driving force is compared to observed grain boundary migration rates in Ni polycrystals for five grain boundary disorientations. Although the stiffness driving force is better correlated to observed migration rates than the curvature driving force, neither correlation is strong. These findings might be the result of a limitation in the theory for grain boundary migration, which treats grain boundaries as independent microstructural entities and ignores the constraints imposed by their connections to other boundaries at triple lines.
{"title":"Can the grain boundary stiffness driving force explain observed grain boundary migration rates in polycrystals?","authors":"Zipeng Xu , Fadi Abdeljawad , Gregory S. Rohrer","doi":"10.1016/j.scriptamat.2025.117135","DOIUrl":"10.1016/j.scriptamat.2025.117135","url":null,"abstract":"<div><div>The anisotropic grain boundary stiffness driving force is compared to observed grain boundary migration rates in Ni polycrystals for five grain boundary disorientations. Although the stiffness driving force is better correlated to observed migration rates than the curvature driving force, neither correlation is strong. These findings might be the result of a limitation in the theory for grain boundary migration, which treats grain boundaries as independent microstructural entities and ignores the constraints imposed by their connections to other boundaries at triple lines.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"274 ","pages":"Article 117135"},"PeriodicalIF":5.6,"publicationDate":"2025-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145735013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-10DOI: 10.1016/j.scriptamat.2025.117139
Yuhao Wang , Haotian Wang , Xiangyu Fu , Yulai Zhu , Sannian Song , Zhitang Song
Amorphous GeAsSe chalcogenides exhibit unique ovonic threshold switching (OTS) behavior for selector devices, yet their performance is limited by structural instability. Herein, we demonstrate that 400 °C annealing induced a liquid-liquid transition (LLT)-like structural reorganization in Ge23As22Se55 glass, leading to remarkable improvements in OTS characteristics. XPS analysis reveals suppressed homopolar bonds and enhanced heteropolar coordination (GeSe4/2, AsSe3/2). Radial distribution functions further evidence local ordering with sharpened As-Se correlations and emergent Se-Se shoulder peaks. This reorganization intensifies Peierls distortion in isolated [AsSe3] units, widening the bandgap by enhancing lone-pair electron localization. Consequently, annealed OTS devices achieve a 45% higher threshold voltage, over 3-order reduction in leakage current, and endurance increased by two orders of magnitude (>108 cycles). Our work can stimulate further exploration of the thermal stability of chalcogenide-based OTS materials, lay a solid foundation for developing LLT-like structural reorganization as a promising strategy for designing thermally stable selectors.
{"title":"Thermally induced structural evolution in amorphous ge-as-se enhances ovonic threshold switching","authors":"Yuhao Wang , Haotian Wang , Xiangyu Fu , Yulai Zhu , Sannian Song , Zhitang Song","doi":"10.1016/j.scriptamat.2025.117139","DOIUrl":"10.1016/j.scriptamat.2025.117139","url":null,"abstract":"<div><div>Amorphous GeAsSe chalcogenides exhibit unique ovonic threshold switching (OTS) behavior for selector devices, yet their performance is limited by structural instability. Herein, we demonstrate that 400 °C annealing induced a liquid-liquid transition (LLT)-like structural reorganization in Ge<sub>23</sub>As<sub>22</sub>Se<sub>55</sub> glass, leading to remarkable improvements in OTS characteristics. XPS analysis reveals suppressed homopolar bonds and enhanced heteropolar coordination (GeSe<sub>4/2</sub>, AsSe<sub>3/2</sub>). Radial distribution functions further evidence local ordering with sharpened As-Se correlations and emergent Se-Se shoulder peaks. This reorganization intensifies Peierls distortion in isolated [AsSe<sub>3</sub>] units, widening the bandgap by enhancing lone-pair electron localization. Consequently, annealed OTS devices achieve a 45% higher threshold voltage, over 3-order reduction in leakage current, and endurance increased by two orders of magnitude (>10<sup>8</sup> cycles). Our work can stimulate further exploration of the thermal stability of chalcogenide-based OTS materials, lay a solid foundation for developing LLT-like structural reorganization as a promising strategy for designing thermally stable selectors.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"274 ","pages":"Article 117139"},"PeriodicalIF":5.6,"publicationDate":"2025-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145735012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-08DOI: 10.1016/j.scriptamat.2025.117134
John Snitzer , Wei-Ying Chen , Xiaoyuan Lou
This study elucidates the evolution of additively manufactured (AM) microstructure of 316H stainless steels (SSs) by direct energy deposition (DED) and laser powder bed fusion (LPBF) during high-temperature dislocation creep . Utilizing in-situ irradiation characterization, the effects of creep-developed microstructures at different stages on the irradiation resistance of AM 316H SS. Precipitates along the prior dislocation cell walls contributed to the resistance to dislocation creep in both materials, with DED 316H being inferior in creep resistance compared to LPBF 316H Under irradiation, dislocation loop formation was observed in both materials within the cell interior. At the doses up to 5 dpa, there was little evidence to support that the creep developed microstructures significantly impact the irradiation resistance of AM 316H SS. It was, however, determined that the processing method itself can affect irradiation resistance. At 5 dpa, the effects of processing condition and creep are no longer observed.
{"title":"Creep-induced microstructural evolution of additively manufactured 316H stainless steels and its effects on radiation resistance","authors":"John Snitzer , Wei-Ying Chen , Xiaoyuan Lou","doi":"10.1016/j.scriptamat.2025.117134","DOIUrl":"10.1016/j.scriptamat.2025.117134","url":null,"abstract":"<div><div>This study elucidates the evolution of additively manufactured (AM) microstructure of 316H stainless steels (SSs) by direct energy deposition (DED) and laser powder bed fusion (LPBF) during high-temperature dislocation creep . Utilizing <em>in-situ</em> irradiation characterization, the effects of creep-developed microstructures at different stages on the irradiation resistance of AM 316H SS. Precipitates along the prior dislocation cell walls contributed to the resistance to dislocation creep in both materials, with DED 316H being inferior in creep resistance compared to LPBF 316H Under irradiation, dislocation loop formation was observed in both materials within the cell interior. At the doses up to 5 dpa, there was little evidence to support that the creep developed microstructures significantly impact the irradiation resistance of AM 316H SS. It was, however, determined that the processing method itself can affect irradiation resistance. At 5 dpa, the effects of processing condition and creep are no longer observed.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"274 ","pages":"Article 117134"},"PeriodicalIF":5.6,"publicationDate":"2025-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145735015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-08DOI: 10.1016/j.scriptamat.2025.117113
Chunguang Tang , Muhammad A. Ghouri , Jiaojiao Yi , Matthew R. Barnett
The Calculation of Phase Diagrams (CALPHAD) method has proven useful in assessing the phase stability of multi-component alloys. This success does not extend to the prediction of stacking fault energy (SFE) in fcc systems. We propose this can be viewed as a consequence of the (largely unknown) compositional dependency of the binary interaction terms. To make the case, we compare CALPHAD-predicted SFEs with atomistic computations based on the axial Ising model. To facilitate the search for new multi-component alloys while acknowledging this shortfall in knowledge, we propose an approach whereby binary interaction terms are refined during the search. As an illustrative case study, we apply this method to a directed search for Cr-Fe-Ni alloys with reduced Ni contents while preserving the value of the SFE.
{"title":"Searching for new multi-component alloys with desirable stacking fault energies: The compositional dependency of binary interaction terms","authors":"Chunguang Tang , Muhammad A. Ghouri , Jiaojiao Yi , Matthew R. Barnett","doi":"10.1016/j.scriptamat.2025.117113","DOIUrl":"10.1016/j.scriptamat.2025.117113","url":null,"abstract":"<div><div>The Calculation of Phase Diagrams (CALPHAD) method has proven useful in assessing the phase stability of multi-component alloys. This success does not extend to the prediction of stacking fault energy (SFE) in fcc systems. We propose this can be viewed as a consequence of the (largely unknown) compositional dependency of the binary interaction terms. To make the case, we compare CALPHAD-predicted SFEs with atomistic computations based on the axial Ising model. To facilitate the search for new multi-component alloys while acknowledging this shortfall in knowledge, we propose an approach whereby binary interaction terms are refined during the search. As an illustrative case study, we apply this method to a directed search for Cr-Fe-Ni alloys with reduced Ni contents while preserving the value of the SFE.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"274 ","pages":"Article 117113"},"PeriodicalIF":5.6,"publicationDate":"2025-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145735014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-06DOI: 10.1016/j.scriptamat.2025.117131
Yibo Zhang , Yaojun Li , Qian Liao , Yuexia Wang , Xianfeng Ma , Fei Zhu , Yuzhou Wang
Conventional nuclear ceramics suffer drastic thermal conductivity degradation under nuclear radiation. MAX phase materials, with their hybrid metallic-ceramic bond characteristics, represent promising fuel materials capable of mitigating irradiation-induced conductivity changes. Nonetheless, the critical property of post-irradiation thermal conductivity of MAX phase remains unexplored. In this study, we investigated the thermal conductivity of Ti3SiC2 following He ion irradiation. Multimodal microstructural characterization revealed irradiation-induced lattice disturbance and a high density of He bubbles. State-of-the-art spatial-domain thermoreflectance measurement demonstrated roughly 74% reduction in thermal conductivity, less severe than conventional ceramics but exceeding typical metals. This intermediate degradation stems from the electron-dominated thermal transport in Ti3SiC2, which is particularly sensitive to small-scale defects. First-principles calculation revealed the distinct impact of irradiation defects on electron transport, with Si and He related defects exhibiting the largest influence. The material’s retained thermal performance under irradiation suggests promising potential for enhancing thermal properties in advanced nuclear fuels.
{"title":"Helium ion induced degradation of microstructure and thermal conductivity in MAX phase Ti3SiC2","authors":"Yibo Zhang , Yaojun Li , Qian Liao , Yuexia Wang , Xianfeng Ma , Fei Zhu , Yuzhou Wang","doi":"10.1016/j.scriptamat.2025.117131","DOIUrl":"10.1016/j.scriptamat.2025.117131","url":null,"abstract":"<div><div>Conventional nuclear ceramics suffer drastic thermal conductivity degradation under nuclear radiation. MAX phase materials, with their hybrid metallic-ceramic bond characteristics, represent promising fuel materials capable of mitigating irradiation-induced conductivity changes. Nonetheless, the critical property of post-irradiation thermal conductivity of MAX phase remains unexplored. In this study, we investigated the thermal conductivity of Ti<sub>3</sub>SiC<sub>2</sub> following He ion irradiation. Multimodal microstructural characterization revealed irradiation-induced lattice disturbance and a high density of He bubbles. State-of-the-art spatial-domain thermoreflectance measurement demonstrated roughly 74% reduction in thermal conductivity, less severe than conventional ceramics but exceeding typical metals. This intermediate degradation stems from the electron-dominated thermal transport in Ti<sub>3</sub>SiC<sub>2</sub>, which is particularly sensitive to small-scale defects. First-principles calculation revealed the distinct impact of irradiation defects on electron transport, with Si and He related defects exhibiting the largest influence. The material’s retained thermal performance under irradiation suggests promising potential for enhancing thermal properties in advanced nuclear fuels.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"274 ","pages":"Article 117131"},"PeriodicalIF":5.6,"publicationDate":"2025-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145683455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号